Gardening & Life by Shannon McKinnon

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Garden Math

A helpful list of garden mathematics to help you count your way to a huge harvest!

With Zones on the left and minimum temperatures on the right the above graph gives you a good idea of what Garden Zone you live in based on the minimum temperature your area experiences during the year. If you want to get real precise, the lowside of Zones are referred to as “a” while the topsides are “b”. So if you experience minus 44 C temperatures you live in 2a; however if it only drops to minus 41 you are in Zone 2b. A minimum of -39 and you are now Zone 3a! Frost free days are also factored in. As northern gardeners are all too aware, minimum temperatures and number of frost free days (the Peace Country gets approximately 85 of those) vary wildly from year to year. Lately we have been nudging closer to Zone 3b despite being labelled as Zone 1b/2b by most experts.

It seems like such a little difference but it makes a big one to trees, shrubs and perennials. You can get by for a few mild years with plants suited for Zone 4 and then whammo! A record breaking cold snap hits and you lose them all. Perennials that die down to the ground every fall and are slow to emerge always have a better chance of survival no matter what the zone. If I love something and it’s labelled Zone 4 or 5 but it dies back to the ground in the fall, I’ll try it anyway. To make it more interesting, a lot of the plant information is wrong. We are happily growing many perennials experts thought would only survive in Zone 5 or even 6.

If you love it and can afford to lose it, I say give it a try!

If you’re watering by hand how much water does each plant need?

Got this helpful bit from wikianswers:

One square foot is 144 square inches, so if you cover that with an inch of water you’ll need 144 cubic inches. One gallon is 231 cubic inches. Dividing 231 by 144 = 0.62 gallons. So a plant growing in about 1 square foot of soil needs a bit more than half a gallon of water a week to equal 1 inch. A 4 ft x 8 ft bed = 32 sq. ft. so at 0.62 gal/sq.ft. you’d want to give it about 20 gallons of water a week.

How much is a ‘yard’ of soil?

Wouldn’t it be great if a yard of soil meant your yard filled with soil? Alas, it actually means a cubic yard – 3 feet by 3 feet by 3 feet which works out to 27 cubic feet. An average sized wheelbarrow will hold approximately six cubic feet which works out to just over four wheelbarrow loads.

How much surface will one yard of soil cover?

To figure out how many square feet one yard of soil will cover simply divide 36 by how thick you want you want your soil in inches and then multiply by nine. So to get six inches of soil spread on your garden the math would be: 36 divided by 6 equals 6 times 9 totals 54 square feet of coverage per yard of soil.

Metric Math – Divide 100 by how thick you want it in centimetres to find out how many square metres a cubic metre will give you.